Good news! With the add-line change that freeze operation on that huge fractal finished! time(img-expr) : cpu time: 1552529 real time: 1567217 gc time: 576576 time(freeze(img)) : cpu time: 26904587 real time: 79234417 gc time: 20568080
What is that, about 7 and a half hours of cpu time, about 22 hours of real time, and about 5.7 hours of gc time? Compared to not even finishing after running for 3 days though, that’s great! https://github.com/AlexKnauth/koch-snowflake/commit/aed7e1ba864ea8a56f3fe296bc684e65d5ee9aa0 On May 5, 2015, at 10:06 AM, Robby Findler <ro...@eecs.northwestern.edu> wrote: > One of the issues is that the racket/draw version is not doing the > cropping that the 2htdp/image version is doing. Changing the > "scene+line" call in utils.rkt to "add-line" cuts the freeze time in > half for me (using size 242 instead of 728 in the time.rkt file). I > didn't check to see if lines go outside the shape, but if they do, you > might consider just using some arithmetic comparisons there in > util.rkt instead. > > With that change, then I see the time for freezing being the same as > the time for the racket/draw version to draw. I tried to find ways to > speed up the construction of the image, but I didn't find anything > that makes a useful change. It seems like just constructing the data > structure that represents the shape has a basic cost and I didn't find > any simple ways to improve the situation inside the library. (I tried > to cut some corners in add-line but to no avail.) > > Sorry, > Robby > > > > On Mon, May 4, 2015 at 10:33 PM, Alexander D. Knauth > <alexan...@knauth.org> wrote: >> >> On May 4, 2015, at 6:02 PM, Robby Findler <ro...@eecs.northwestern.edu> >> wrote: >> >> Another approach here would be to help me do performance debugging of >> 2htdp/image :). You could write the code directly as imperative calls >> to the dc<%> interface and see how that compares. If there's a >> significant difference, that suggests we might be able to find a way >> to speed up 2htdp/image. >> >> >> I tried doing that, and here’s what I got: >> (time (snowflake/inner-fractal 728)) : cpu time: 14775 real time: 14874 >> gc time: 2304 >> (time (freeze img1)) : cpu time: 377110 real time: >> 377867 gc time: 198343 >> (time (snowflake/inner-fractal/draw 728)) : cpu time: 24257 real time: 24267 >> gc time: 5852 >> Where snowflake/inner-fractal uses 2htdp/image, the result of that call is >> defined as img1, and snowflake/inner-fractal/draw uses racket/draw. >> The program that produces this output is here: >> https://github.com/AlexKnauth/koch-snowflake/blob/master/try-draw/time.rkt >> >> > > -- > You received this message because you are subscribed to the Google Groups > "Racket Users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to racket-users+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
